Tim Cook has acknowledged that Apple has bought back $14 billion of its own shares over the past two weeks — reacting to an 8 percent decline in shares following the recent financial quarter results.

In an interview with the Wall Street Journal, Cook admitted that he was “surprised” by Wall Street’s reaction to Apple’s last quarter, in which the company broke records by selling 77 million iOS devices over the holiday season.

Apple’s recent share repurchase is the largest of its kind for a company of Apple’s size over a similar timespan. During the past 12 months, Apple has bought back $40 billion of its own shares — part of a plan to repurchase a total of $60 billion. In the past two weeks Cook says that Apple bought $12 billion of its shares through an “accelerated” repurchase program, and a further $2 billion on the open market. Apple plans to disclose updates to its buyback program either next month or in April.